Late Endosomes Act as mRNA Translation Platforms and Sustain Mitochondria in Axons

Local translation regulates the axonal proteome, playing an important role in neuronal wiring and axon maintenance. How axonal mRNAs are localized to specific subcellular sites for translation, however, is not understood. Here we report that RNA granules associate with endosomes along the axons of retinal ganglion cells. RNA-bearing Rab7a late endosomes also associate with ribosomes, and real-time translation imaging reveals that they are sites of local protein synthesis. We show that RNA-bearing late endosomes often pause on mitochondria and that mRNAs encoding proteins for mitochondrial function are translated on Rab7a endosomes. Disruption of Rab7a function with Rab7a mutants, including those associated…

• WT
  Wellcome Trust

  Awards: 203249/Z/16/Z, 085314/Z/08/Z
• E
  EMBO
• NO
  Nederlandse Organisatie voor Wetenschappelijk Onderzoek
• SD
  Studienstiftung des Deutschen Volkes
• GC
  Gates Cambridge Trust
• NS
  Natural Sciences and Engineering Research Council of Canada
• BA
  Biotechnology and Biological Sciences Research Council

  Awards: BB/N006402/1, BB/N006402/1
• ER
  European Research Council

  Award: 322817